Step-by-step explanation:
P = 2l + 2w
1. P = 2(18) + 2(12)
P = 36 + 24
P = 60
2. P = 2(20) + 2(20)
P = 40 + 40
P = 80
P = l + l + l
3. P = 14 + 10 + 15
P = 39
P = s + s + s + s
4. P = 8 + 6 + 10 + 6
P = 30
P = 2l + 2w
5. P = 2(24) + 2(18)
P = 48 + 36
P = 84